Take the war in Iraq. Bayh, like most of his Democratic Senate colleagues weighing a presidential bid in 2008, initially supported the 2002 use-of-force resolution against Iraq. But unlike some of his rivals, Bayh has so far been unwilling to either fully repudiate that vote or set hard deadlines for withdrawing U.S. troops from the country.

"We've got to be somewhere between 'cut and run'...and mindlessly staying the course," Bayh said during an interview with several Washington Post journalists in mid-February. "You've got to have a sensible middle ground."

That's Evan Bayh in a nutshell -- advocating the "sensible middle ground." By any judgment, Bayh has perhaps the most extensive and impressive resume of the Democrats considering a presidential bid in 2008 -- elected twice as governor of Indiana, a state carried by Republicans in every presidential election since 1964, and now in his second Senate term. But is an impressive resume enough? Democratic voters seemed to vote with their head (nominating John Kerry) over their heart (rejecting liberal firebrand Howard Dean) in the 2004 primaries and still wound up on the short end of the presidential race.

Will electability trump ideology again in 2008? Bayh is staking much on a bet that it will.

Never a charismatic politician, Bayh is hoping that voters see that serious times call for serious politicians -- a philosophy of bridge-building over bomb-throwing. "Leading this country has to be about something other than ideological division," Bayh said. "It's got to be about how we move this country forward in practical terms, not looking at issues as left or right or even center but instead do they make sense, will they matter in peoples' lives?"

That's not to say, Bayh argues, that he is simply "Republican lite" as his critics on the party's ideological left have dubbed him. "I've got a long record of standing for progressive things that help to empower people to meet the challenges they confront," said Bayh -- rattling off a list of examples from improving schools to expanding health care to balancing the budget.

Bayh, too, has cast several votes in recent months sure to boost his credentials among party liberals -- most notably his votes against Supreme Court Justices John Roberts, an Indiana native, and Samuel A. Alito Jr. Bayh also supported a failed filibuster attempt against Alito.

Asked about those votes, Bayh said his quibble was as much with the process and the attitude that President Bush took toward it rather than the individual nominees. "When [Bush] ran for office he essentially gave a wink and a nod to the most extreme elements in his own party," said Bayh, explaining that to his way of thinking the president was "giving an indication that he had an ideological agenda, and that raised the bar in my mind."

As Bayh sees it, Supreme Court nominees are taught to obfuscate rather than illuminate their issues positions when questioned by the Judiciary Committee. "It's very uncommon to get direct, precise answers given the nature of the process we have because it's politicized to such a degree," Bayh said.

Although Bayh has grown increasingly comfortable discussing his progressive portfolio, he is at his best when discussing an issue outside of Democrats' comfort zone -- national security.

Bayh made a speech in early February at the Center for Strategic and International Studies in Washington arguing that security was a "threshold" issue for many voters when assessing Democrats and that his party could no longer try to change the subject when attacked by Republicans on it.

"The majority of Americans don't trust us with their lives, much less with other things, and events are unfortunately likely to occur that will remind the American people that this is a dangerous world," said Bayh. He added that Karl Rove, the White House deputy chief of staff, had made clear that the 2006 elections will come down to a simply statement: "Vote for [Republicans] or you will die."

Faced with that sort of rhetoric, Bayh said the only solution is to engage in a "head on" refutation of that idea; "There is a long and compelling case to be made that they have undermined our nation's security, that they, in fact, are weak on what they claim to be strong on. And we have got to take that on and hammer that."

Aside from constructing a presidential policy portfolio around security issues, the growing economic threat from China and the import of recognizing the impact of the ever-expanding global economy, Bayh is also deeply engaged in the nuts-and-bolts process of building a national political infrastructure for the 2008 campaign.

He has been the most active of the would-be 2008 candidates in the behind-the-scenes courtship of key grassroots activists and financial heavy-hitters -- traveling the country in order to make his case to these influential footsoldiers. That hard work has paid dividends as Bayh raised better than $3 million for his Senate committee in 2005, ending the year with a whopping $9.5 million on hand -- all of which could be directly transferred to a presidential bid. He also raked in an additional $1.5 million for his All America political action committee, a sum that can be used to support Democratic candidates in 2006 and fund Bayh's travels around the country.

Bayh has also put together an extremely strong inner circle of political advisers with experience running national campaigns. Anita Dunn, Bayh's media consultant, was a lead strategist for former New Jersey Sen. Bill Bradley's 2000 presidential race. Paul Maslin, Bayh's pollster, provided the survey research for Dean's insurgent bid in 2004.

Despite appearances, Bayh insists he has not made a final decision on 2008. "I am doing the practical things that you would expect someone to do to make possible a decision about running for president," said Bayh. "Regrettably, the process starts so early these days that if you don't do some of these things you essentially decide not to, and so I am going forward and doing them."

He said no final decision will come until after the midterm elections this fall.

(Video excerpts of the Bayh interview are here; the full transcript is here. For more on Bayh, check out a profile I wrote of him for Indianapolis Monthly magazine last year.)